Solar energy systems have been used to provide electricity and heat for decades. Designers of all types of energy generation systems continually strive to improve output power efficiency. One current problem in a solar cell energy conversion system is the efficient extraction of low-cost electricity. The conversion efficiency of a photovoltaic cell is the proportion of sunlight energy that the cell converts to electrical energy. Improving efficiency is vital to producing solar cells that are competitive with traditional energy sources, such as fossil fuels and nuclear power. The efficiency of solar cells has increased substantially for the earliest conventional photovoltaic devices from about 1 to 2% efficiency. Current conventional photovoltaic systems convert 7% to 17% of light energy into electrical energy.
What is first needed is a system and method for converting energy in a solar cell with extremely high efficiency. What are also needed are solar cell materials and structures, and solar cell fabrication procedures that are inexpensive while attaining high levels of efficiency in energy generation. A further need is a solar cell configuration that permits collection of concentrated sunlight energy for conversion to electricity to increase output power generation.
Solar cells operating in liquid have an increased operating efficiency resulting from two independent physical phenomena, an increase in output current from the solar cells from simply wetting the solar cells, and enhanced collection of light through refraction and inner reflection of light in the liquid. Dielectric liquids are found to increase energy conversion efficiency of n/p junction solar cells and also function as a medium for optical concentration. The properties of dielectric liquid permit the construction of a solar cell panel with a suitable geometry for functioning as an optical concentrator.
An organic dielectric liquid immersing one or more junction photovoltaic cells increases the energy conversion efficiency of the photovoltaic cells. The organic dielectric liquid also is a highly suitable medium for usage as an optical concentrator. The organic dielectric liquid in combination with the junction photovoltaic cells operates as a highly efficient and low-cost optical concentrator.
According to one aspect of the present invention, the energy conversion efficiency of a solar cell or photovoltaic cell is increased by wetting of the surfaces of the cell with a dielectric liquid.
According to another aspect of the present invention, a solar panel configured as an encapsulation system containing photovoltaic cells and organic dielectric liquid increases the output power of a solar cell or photovoltaic cell. The solar panel has a suitable geometry for refracting illumination through the organic dielectric liquid to further increase the output power. For example, panel walls have suitable transparency for operation as a light beam collector. Illumination collected through the light beam collector refracts at the boundary of the organic dielectric liquid and enhances the photoelectric effect of the photovoltaic cells.
According to another aspect of the present invention, wetting of the solar cells with the organic dielectric liquid in combination with configuration of the solar panels as encapsulation system with walls operating as light beam collectors greatly improves output power and reduces cost per watt.
According to a further aspect of some embodiments of the present invention, the solar panel can be in the form of a low height dome or cylindrical structure with a substantially flat panel tray covering a first end of the cylinder and a panel cover or lid covering a second end of the cylinder. All or a portion of the panel walls and the panel lid are transparent for functionality as a light collector. The horizontal cross-section of the cylinder can have any suitable shape such as a circle, an ellipse, an oval, an egg-shape, a rectangle, a triangle, and a square. The horizontal cross-section of the cylinder can be symmetric or asymmetric.
Any organic dielectric liquid, whether polar or nonpolar, is suitable for usage in a solar panel. Greater energy conversion efficiency is attained for a polar organic dielectric liquid with increasing efficiency for liquids with a relatively higher index of refraction. The organic dielectric liquid can be further selected based on the melting point and the boiling point of various liquids for solar energy systems according to seasonal weather and climate of practical usage. For example, the liquid can be selected based on values of the lowest and highest temperature of the geographical area in which the solar energy system is used.
According to another aspect of the present invention, an increase in output power from a solar cell or photovoltaic cell, both of which use p-n junctions, can be obtained by deposition of a solid dielectric film, the dipoles of which are polarized perpendicular to the surface planes of the solar cell over the surfaces of the solar cell.